title: MLS-2384, a new 6-bromoindirubin derivative with dual JAK/Src kinase inhibitory activity, suppresses growth of diverse cancer cells.
abstract: Janus kinase (JAK) and Src kinase are the two major tyrosine kinase families upstream of signal transducer and activator of transcription (STAT). Among the seven STAT family proteins, STAT3 is constitutively activated in many diverse cancers. Upon activation, JAK and Src kinases phosphorylate STAT3, and thereby promote cell growth and survival. MLS-2384 is a novel 6-bromoindirubin derivative with a bromo-group at the 6-position on one indole ring and a hydrophilic group at the 3'-position on the other indole ring. In this study, we investigated the kinase inhibitory activity and anticancer activity of MLS-2384. Our data from in vitro kinase assays, cell viability analyses, western blotting analyses, and animal model studies, demonstrate that MLS-2384 is a dual JAK/Src kinase inhibitor, and suppresses growth of various human cancer cells, such as prostate, breast, skin, ovarian, lung, and liver. Consistent with the inactivation of JAK and Src kinases, phosphorylation of STAT3 was inhibited in a dose-dependent manner in the cancer cells treated with MLS-2384. STAT3 downstream proteins involved in cell proliferation and survival, such as c-Myc and Mcl-1, are downregulated by MLS-2384 in prostate cancer cells, whereas survivin is downregulated in A2058 cells. In these two cancer cell lines, PARP is cleaved, indicating that MLS-2384 induces apoptosis in human melanoma and prostate cancer cells. Importantly, MLS-2384 suppresses tumor growth with low toxicity in a mouse xenograft model of human melanoma. Taken together, MLS-2384 demonstrates dual JAK/Src inhibitory activity and suppresses tumor cell growth both in vitro and in vivo. Our findings support further development of MLS-2384 as a potential small-molecule therapeutic agent that targets JAK, Src, and STAT3 signaling in multiple human cancer cells.
authors.affiliation: Beckman Research Institute; City of Hope Comprehensive Cancer Center; Duarte, CA USA.
authors.forename: Lucy
authors.initials: L
authors.lastname: Liu
authors.affiliation: Pharmacognosy and Natural Products Chemistry; University of Athens; Athens, Greece.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gaboriaud
authors.affiliation: Pharmacognosy and Natural Products Chemistry; University of Athens; Athens, Greece.
authors.forename: Konstantina
authors.initials: K
authors.lastname: Vougogianopoulou
authors.affiliation: Beckman Research Institute; City of Hope Comprehensive Cancer Center; Duarte, CA USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Beckman Research Institute; City of Hope Comprehensive Cancer Center; Duarte, CA USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Wu
authors.affiliation: Beckman Research Institute; City of Hope Comprehensive Cancer Center; Duarte, CA USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.affiliation: Pharmacognosy and Natural Products Chemistry; University of Athens; Athens, Greece.
authors.forename: Leandros
authors.initials: L
authors.lastname: Skaltsounis
authors.affiliation: Vaccine & Gene Therapy Institute of Florida; Port St. Lucie, FL USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Jove
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D005260:Female; D064593:Heterografts; D006801:Humans; D007211:Indoles / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D053614:Janus Kinase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D007211:Indoles; C000592914:MLS-2384; D050796:STAT3 Transcription Factor; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D053614:Janus Kinase 2; D019061:src-Family Kinases
keywords: JAK; STAT3; Src; apoptosis; bromoindirubin; cancer cells; indirubin